scsi: ufs: Add checks before setting clk-gating states

Clock gating can be turned on/off selectively which means the associated
state information is only correct if the feature is enabled. This change
makes sure that we only look at state of clk-gating if it is enabled.

Link: https://lore.kernel.org/r/1596975355-39813-2-git-send-email-cang@codeaurora.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 30762228423981253c7cf4908feca8d99d51543b..5acb38ca03f9160f44d8e5b123e282ba937f1e28 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1839,6 +1839,8 @@ static void ufshcd_init_clk_gating(struct ufs_hba *hba)
        if (!ufshcd_is_clkgating_allowed(hba))
                return;
 
+       hba->clk_gating.state = CLKS_ON;
+
        hba->clk_gating.delay_ms = 150;
        INIT_DELAYED_WORK(&hba->clk_gating.gate_work, ufshcd_gate_work);
        INIT_WORK(&hba->clk_gating.ungate_work, ufshcd_ungate_work);
@@ -2541,7 +2543,8 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
                err = SCSI_MLQUEUE_HOST_BUSY;
                goto out;
        }
-       WARN_ON(hba->clk_gating.state != CLKS_ON);
+       WARN_ON(ufshcd_is_clkgating_allowed(hba) &&
+               (hba->clk_gating.state != CLKS_ON));
 
        lrbp = &hba->lrb[tag];
 
@@ -8326,8 +8329,11 @@ disable_clks:
                /* If link is active, device ref_clk can't be switched off */
                __ufshcd_setup_clocks(hba, false, true);
 
-       hba->clk_gating.state = CLKS_OFF;
-       trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state);
+       if (ufshcd_is_clkgating_allowed(hba)) {
+               hba->clk_gating.state = CLKS_OFF;
+               trace_ufshcd_clk_gating(dev_name(hba->dev),
+                                       hba->clk_gating.state);
+       }
 
        /* Put the host controller in low power mode if possible */
        ufshcd_hba_vreg_set_lpm(hba);
@@ -8467,6 +8473,11 @@ disable_irq_and_vops_clks:
        if (hba->clk_scaling.is_allowed)
                ufshcd_suspend_clkscaling(hba);
        ufshcd_setup_clocks(hba, false);
+       if (ufshcd_is_clkgating_allowed(hba)) {
+               hba->clk_gating.state = CLKS_OFF;
+               trace_ufshcd_clk_gating(dev_name(hba->dev),
+                                       hba->clk_gating.state);
+       }
 out:
        hba->pm_op_in_progress = 0;
        if (ret)